天美传媒

Abstract

Three strains of fungi were isolated and identified as Aspergillus flavus, Aspergillus awamori and Aspergillus tubingensis showed good enzyme activity on casein, 1562,5 U., 1357,14 U. and 2155,55 U. respectively. After purification by molecular exclusion chromatography, affinity chromatography and SDS-PAGE helped find three enzymes having approximately molecular weight of 35KDa for A. flavus and 55KDa for A. awamori and A. tubingensis. The optimum pH of activity is 5, 4.5 and 4.0 and the optimum temperature of activity is 35癈, 40癈 and 30癈 for A. flavus, A. awamori and A. tubingensis respectively. These enzymes used to coagulate fresh cow milk, showed that the milk-coagulation time compared with rennet coagulation time was very short, in the same conditions of coagulation. Curd firmness and brightness are very interesting, the pH of different curds is measured and several parameters determined to highlight the industrial interests of the produced enzymes.

Biography

T hree strains of fungi were isolated and identified as Aspergillus flavus, Aspergillus awamori and Aspergillus tubingensis showed good enzyme activity on casein, 1562,5 U., 1357,14 U. and 2155,55 U. respectively. After purification by molecular exclusion chromatography, affinity chromatography and SDS-PAGE helped find three enzymes having approximately molecular weight of 35KDa for A. flavus and 55KDa for A. awamori and A. tubingensis. The optimum pH of activity is 5, 4.5 and 4.0 and the optimum temperature of activity is 35癈, 40癈 and 30癈 for A. flavus, A. awamori and A. tubingensis respectively. These enzymes used to coagulate fresh cow milk, showed that the milk-coagulation time compared with rennet coagulation time was very short, in the same conditions of coagulation. Curd firmness and brightness are very interesting, the pH of different curds is measured and several parameters determined to highlight the industrial interests of the produced enzymes.